1. Field of the Invention
This invention relates generally to apparatus for selectively removing articles from a conveyor. More specifically, it concerns a suction diverter that operates intermittently, and when activated, moves laterally above the conveyor for guiding acceptable articles therealong and for guiding rejected articles therefrom.
2. Description of the Prior Art
Vacuum starwheels have been used for diverting articles, such as bottles, into one of a number of conveyor lines. Examples of such vacuum starwheels are disclosed by U.S. Pat. Nos. 4,391,372, issued July 5, 1983 to Fredrick L. Calhoun; 3,279,599, issued Oct. 18, 1966 to J. G. Drennan; and 2,800,226, issued July 23, 1957 to J. G. Drennan. These starwheels operate continuously contacting every bottle passing through, while the number of reject bottles can be relatively few. This continuous use increases wear on the vacuum starwheels. Some starwheels are turned by frictional contact with bottles moving along the conveyor. Thus, they require filling multiple pockets with bottles until sufficient friction builds up between the bottles and the conveyor to overcome the friction on the starwheels contacting the bottles. Slippage of bottles on the conveyor and back-up of bottles at a starwheel interfer with any control timing based upon conveyor speed between between an inspection station and the starwheel.
Starwheels limit the use of bottle sorting equipment to a narrow range of bottle sizes that interfit within pockets of the starwheels. It is desirable to provide more versatility for sorting equipment to handle various sized bottles. A problem with diverters that move laterally above a conveyor is obstructing the flow of articles. A moving article that contacts the diverter, an adjacent guide rail, or another article, often alters speed. That limits the use of control timing based upon conveyor speed. Thus, it is desirable for the diverter to guide articles moving along the conveyor at a constant speed corresponding to conveyor speed.